The major basic research focus of this laboratory involves this project, with the following goals: 1) to identify, map and characterize varicella-zoster virus genes and proteins active in latent or productive infections. 2) to define the temporal sequence of gene expression. 3) to determine the interaction of antiviral drugs with viral gene products through a molecular analysis of drug-resistant mutants. 4) to characterize the molecular epidemiology of varicella-zoster virus infections. To accomplish these ends we have constructed recombinant libraries of the complete VZV genome in a variety of vectors. The genome and most, if not all, of the major viral messages have been identified and preliminarily mapped, and two gene products representing immediate early and early functions have been identified and located. Our current efforts are directed at finer mapping of selected viral transcripts, defining the temporal sequence of gene expression using cell-free virus, and utilizing herpes simplex virus mutants to help identify and map complementary VZV gene functions in the establishment of an in situ hybridization system using a 35S riboprobe for detection of latent sequences within human trigeminal ganglia.